Association between F protein and negative costimulatory molecule 2B4 in chronic HCV infection

Objective To investigate the relationship between the production of hepatitis C virus (HCV) F protein and the negative costimulatory molecule 2B4 in chronic HCV infection. Methods The blood samples of chronic hepatitis patients (CHP) were collected and the positive rate of F antibody (F-Ab) was detected and divided into HCV-F(+) and HCV-F(-). Blood samples collected from healthy volunteers were used as control group. Peripheral blood mononuclear cells (PBMCs) were isolated and cultured.The levels of interleukin 4 (IL-4),interferon γ (IFN-γ) before and after the blockade of 2B4 antibody were detected by enzyme-linkead immunosorbent assay. Results The levels of IFN-γ and IL-4 secreted in HCV patients were significantly higher than those in healthy controls (all P<0.05), and the level of IFN-γ secreted in HCV-F (-) group was significantly higher than that of HCV-F (+) group (F=1.908,P=0.020), while the level of IL-4 secretion was lower than that of HCV-F (+) group (F=1.342,P=0.009). After blocking with 2B4 antibody, the level of IFN-γ and IL-4 in healthy group had no significant change (all P>0.05). The level of IFN-γ in CHP group was significantly higher than that in the control group (F=1.214,P=0.003), and the levels in HCV-F (-) was higher than that of HCV-F (+) group (F=1.434,P=0.009). The levels of IL-4 were significantly lower than those before antibody block (F=1.505,P=0.015), and the levels in HCV-F (-) group were lower than those in HCV-F (+) group (F=1.444,P=0.032). Conclusions In chronic HCV infection, the signal regulation mechanism of F protein is correlated with negative costimulatory molecule 2B4.